A standard key-controlled lock has a cylinder whose core can be rotated by an appropriately bitted key to turn an actuating element linked to a retractable bolt or the like. The right key is inserted in the cylinder to rotate its core and actuate the lock. On the inside of the door the lock can have a knob that is also connected to the actuator so that the bolt can be extended or retracted from inside without using the key.
In a powered lock a code is entered or key employed to operate a motor that itself extends or retracts the bolt. Such a system is frequently employed, for example, in bank safe-deposit boxes or as remote door openers. In order to allow the lock to be used when power fails or the lock's battery runs down, such a lock is frequently provided with a manual override.
All such systems are fairly complex and expensive to manufacture. None is flexible and easily retrofitted to the other.